▎ 摘　　要

NOVELTY - Preparation of germanium quantum dot involves cleaning a substrate to remove contaminants on substrate surface, transferring 1-10 single atomic graphene layers on cleaned substrate and growing 1-10 nm thickness germanium quantum dot on graphene layer at room temperature. USE - The method is useful for preparing germanium quantum dot, which is useful in photodetector element. ADVANTAGE - The method ensures simple preparation of germanium quantum dot with high density, reduced size and matrix elements, without performing annealing process and without defects.